CN110718440B - Atomic layer etching equipment and etching method - Google Patents

Abstract

The embodiment of the application provides atomic layer etching equipment and an etching method. The atomic layer etching equipment comprises: the plasma processing device comprises a process chamber, an upper radio frequency assembly and an auxiliary plasma generating device; the upper radio frequency assembly is used for applying radio frequency power to the process chamber so as to excite the process gas entering the process chamber into plasma; the auxiliary plasma generating device is used for delivering electrons into the process chamber so as to stabilize the plasma in an inductive coupling discharge mode. According to the embodiment of the application, the process chamber can rapidly enter the inductive coupling discharge mode, the time for the plasma to enter the inductive coupling discharge mode is shortened, the time of each operation period of the atomic layer is shortened, and therefore the atomic layer etching efficiency and the process yield are improved.

Description

Atomic layer etching equipment and etching method

Technical Field

The application relates to the technical field of atomic layer etching, in particular to atomic layer etching equipment and an atomic layer etching method.

Background

At present, in the atomic layer etching process, a chemically active gas (such as chlorine) and an inert gas (such as argon) need to be respectively introduced, and an inductive coupling discharge mode is generally adopted as a discharge mode. An atomic layer etch process generally includes four steps in one cycle of operation: (1) an adsorption step, exposing the surface of the substrate to reaction gas, introducing process gas into the process chamber, ionizing to form weak plasma, and adsorbing active particles and forming an adsorption layer by the process gas; (2) a removing step, wherein residual process gas in the reaction is removed; (3) etching, namely exposing the adsorption layer to inert gas, ionizing the inert gas to form plasma, bombarding the surface of the substrate by the inert ions to generate sputtering, and removing atoms on the top layer of the substrate; (4) a clearing step: and removing the etching products to finish an operation period.

However, in the prior art, the atomic layer etching generally applies radio frequency power to the induction coil by using a radio frequency power supply, the reaction cavity generates an induction magnetic field, the magnetic field generates an induction electric field according to the faraday's law of induction, electrons are accelerated to continuously collide with atoms or molecules and are ionized to form plasma, and therefore the absorption of the radio frequency power is realized through the coupling between the coil and the plasma. For the low coil current, the plasma discharge is in the capacitive coupling discharge mode, the electron density is gradually increased after the absorbed power reaches the maximum value along with the increase of the coil current, and the plasma discharge is in the inductive coupling discharge modeQuickly exceeds 10¹⁶m^-3. In actual etching, the plasma is required to work in an inductive coupling discharge mode, but the time from plasma glow starting to plasma stable state reaching through matching, namely the inductive coupling discharge mode, is usually 5-15 seconds, which is difficult to realize the requirement of the atomic layer etching process, in one operation period of the atomic layer etching process, the adsorption and etching steps are required to be only 2-12 seconds, if the plasma glow starting time is too long, a large amount of time needs to be consumed in each operation period, so that the etching efficiency is too low, in addition, residual gas in each step is incompletely removed, and the process quality is also seriously influenced.

Disclosure of Invention

The application provides atomic layer etching equipment and an etching method aiming at the defects of the existing mode, and aims to solve the technical problems of incomplete etching efficiency and residual gas removal in the prior art.

In a first aspect, an embodiment of the present application provides an atomic layer etching apparatus, including: the plasma processing device comprises a process chamber, an upper radio frequency assembly and an auxiliary plasma generating device; the upper radio frequency assembly is used for applying radio frequency power to the process chamber so as to excite the process gas entering the process chamber into plasma; the auxiliary plasma generating device is used for delivering electrons into the process chamber so as to stabilize the plasma in an inductive coupling discharge mode.

In one embodiment of the present application, the auxiliary plasma generating device includes a generator and a transmitter, and the generator is connected to the process chamber through the transmitter.

In an embodiment of the present application, the auxiliary plasma generating apparatus further includes a ballast electrically connected to the generator for adjusting a current of the generator.

In one embodiment of the present application, the generator is an ultraviolet lamp.

In one embodiment of the present application, the generator is an electron gun, and the conveyor vacuum-transports a medium; the electron gun is used for generating an electron beam and transmitting the electron beam into the process chamber through the vacuum transmission medium.

In an embodiment of the application, the atomic layer etching apparatus further includes a monitoring device, and the monitoring device is disposed in the process chamber and is configured to monitor a discharge mode of a plasma in the process chamber.

In an embodiment of the present application, the atomic layer etching apparatus further includes a lower rf assembly, and a susceptor for supporting a substrate is disposed in the process chamber; the lower radio frequency assembly comprises a lower radio frequency power supply and a lower matcher, wherein the lower radio frequency power supply is connected with the base through the lower matcher and is used for forming a bias electric field on the base.

In a second aspect, an embodiment of the present application provides an atomic layer etching method, which is applied to the atomic layer etching apparatus provided in the first aspect, and includes the following steps:

and an adsorption step, namely introducing first process gas into the process chamber, starting the upper radio frequency assembly and the auxiliary plasma generating device, and controlling the working state of the auxiliary plasma generating device according to the discharge mode of the plasma in the process chamber so as to stabilize the plasma in the inductive coupling discharge mode.

And a removing step, namely closing the auxiliary plasma generating device and removing the first process gas.

And etching, namely introducing a second process gas into the process chamber, starting the upper radio frequency assembly and the auxiliary plasma generating device, and controlling the working state of the auxiliary plasma generating device according to the discharge mode of the plasma.

And a cleaning step of cleaning the second process gas and the etching product.

In one embodiment of the present application, whether the plasma is stable in the inductive coupling discharge mode is monitored and determined; if yes, the auxiliary plasma generating device is closed; otherwise, adjusting the power of the auxiliary plasma generating device to stabilize the plasma in the inductive coupling discharge mode.

In an embodiment of the present application, the first process gas is a reactive gas, and the second process gas is an inert gas.

The technical scheme provided by the embodiment of the application has the following beneficial technical effects:

by the aid of the auxiliary plasma generation device, the process chamber can quickly enter the inductive coupling discharge mode on the basis of work of the upper radio frequency assembly, time for the plasma to enter the inductive coupling discharge mode is shortened, time of each operation period of the atomic layer is shortened, and accordingly atomic layer etching efficiency and process yield are improved. Furthermore, due to the adoption of the design, the plasma starting state in the removing step in the prior art can be avoided, the residual process gas can be more thoroughly removed after each step of the operation period, the reaction separation among the steps required by the atomic layer etching process is really realized, and the accurate control on the process damage and the uniformity is facilitated.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The foregoing and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of an atomic layer etching apparatus according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a generator and process chamber configuration according to an embodiment of the present disclosure;

fig. 3 is a schematic flowchart of an atomic layer etching method according to an embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to the present application, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar parts or parts having the same or similar functions throughout. In addition, if a detailed description of the known art is not necessary for illustrating the features of the present application, it is omitted. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

It will be understood by those within the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The following describes the technical solutions of the present application and how to solve the above technical problems with specific embodiments.

In a first aspect, an embodiment of the present application provides an atomic layer etching apparatus, a schematic structural diagram of which is shown in fig. 1, including: the plasma processing device comprises aprocess chamber 1, an upper radio frequency assembly 2 and an auxiliary plasma generating device 3; the upper radio frequency assembly 2 is used for applying radio frequency power to theprocess chamber 1 so as to excite the process gas entering the process chamber into plasma; the auxiliary plasma generating device 3 is used to deliver electrons into theprocess chamber 1 to stabilize the plasma in the inductively coupled discharge mode.

As shown in fig. 1, theprocess chamber 1 may be a reaction chamber made of aluminum alloy or stainless material and capable of being maintained in a vacuum state. In practical applications, theprocess chamber 1 may be introduced with at least two process gases, such as a reactive gas and an inert gas, which is not limited in the embodiments of the present application. The upper rf assembly 2 may be a coupled discharge mode assembly, and the upper rf assembly 2 may be disposed outside theprocess chamber 1 and apply rf power into theprocess chamber 1 to excite the process gas entering theprocess chamber 1 into plasma and to make theprocess chamber 1 in a capacitively coupled discharge mode. The auxiliary plasma generating device 3 can input electrons into theprocess chamber 1, so that the process gas can be excited into plasma, the speed of theprocess chamber 1 entering an inductive coupling discharge mode is improved, and the plasma can be in the inductive coupling discharge mode so as to facilitate the atomic layer etching process.

By the aid of the auxiliary plasma generation device, the process chamber can quickly enter the inductive coupling discharge mode on the basis of work of the upper radio frequency assembly, time for the plasma to enter the inductive coupling discharge mode is shortened, time of each operation period of the atomic layer is shortened, and accordingly atomic layer etching efficiency and process yield are improved. Furthermore, due to the adoption of the design, the plasma starting state in the removing step in the prior art can be avoided, the residual process gas can be more thoroughly removed after each step of the operation period, the reaction separation among the steps required by the atomic layer etching process is really realized, and the accurate control on the process damage and the uniformity is facilitated.

It should be noted that the embodiments of the present application are not limited to the specific implementation of theprocess chamber 1 and the upper rf assembly 2, and for example, theprocess chamber 1 may be made of other corrosion-resistant materials. Therefore, the embodiments of the present application are not limited thereto, and those skilled in the art can adjust the settings according to actual situations.

In one embodiment of the present application, the auxiliary plasma generating device 3 comprises agenerator 31 and aconveyor 32, wherein thegenerator 31 is connected to theprocess chamber 1 through theconveyor 32. As shown in fig. 1, thegenerator 31 may be disposed outside theprocess chamber 1, and various types ofelectron generators 31 may be used, which is not limited in the embodiments of the present application. Atransmitter 32 may be disposed between thegenerator 31 and theprocess chamber 1, and may transmit electrons or electron beams generated by thegenerator 31 to the inside of theprocess chamber 1. Theconveyor 32 may specifically adopt a vacuum conveying system cooperating with thegenerator 31, but the application is not limited thereto, and the setting can be adjusted by those skilled in the art according to the actual situation. By adopting the design, the embodiment of the application has the advantages of simple structure, convenient application and effectively reduced application cost.

It should be noted that the embodiments of the present application are not limited to the specific implementation of thegenerator 31 and theconveyor 32, for example, thegenerator 31 may also be directly disposed in theprocess chamber 1, and theconveyor 32 is not required to achieve the above functions. Therefore, the embodiments of the present application are not limited thereto, and those skilled in the art can adjust the settings according to actual situations.

In an embodiment of the present application, the auxiliary plasma generating device 3 further comprises a ballast, which is electrically connected to thegenerator 31 and is used for adjusting the current of thegenerator 31. Alternatively, thegenerator 31 is an ultraviolet lamp.

As shown in fig. 1, when thegenerator 31 is an ultraviolet lamp, the auxiliary plasma generating device 3 may further include a ballast (not shown). Specifically, when the ultraviolet lamp is used, a large number of electrons are emitted from filaments at two ends of the lamp tube and are conveyed into theprocess chamber 1 through theinternal conveyer 32, the electrons move back and forth under the action of the high-voltage alternating electric field, and if the energy of the electrons is enough, impact ionization is generated when the electrons collide with process gas atoms, so that the collided electrons and gas ions are added under the action of the electric field to move to knock out more ions, and plasma is formed. Because the charged charges in the lamp tube of the ultraviolet lamp move back and forth to form current under the action of the alternating electric field applied to the two end electrodes of the ultraviolet lamp, in order to avoid overlarge current, the current can be limited by the ballast to increase so as to keep the current in a balanced state, thereby improving the stability. By adopting the design, the ultraviolet lamp is arranged, so that the time for the plasma to enter the inductive coupling discharge mode can be effectively shortened, the operation cycle time of the atomic layer etching process can be effectively shortened, and the process yield is further improved. In addition, the cost can be effectively reduced due to the adoption of the ultraviolet lamp, so that the economic benefit is improved. Furthermore, in practical application, when the power in the adsorption step is sufficient, only an ultraviolet lamp can be used for generating plasma, so that only the etching step needs an inductive coupling discharge mode in one operation period, and the difficulty in realizing the atomic layer etching process is effectively reduced.

It should be noted that not all embodiments of the present application necessarily include a ballast, and in some other embodiments, a ballast may not be included, as long as a similar function can be achieved. Therefore, the embodiments of the present application are not limited thereto, and those skilled in the art can adjust the settings according to actual situations.

In one embodiment of the present application, thegenerator 31 is an electron gun, and thetransmitter 32 is a vacuum transmission medium; an electron gun is used to generate an electron beam and deliver it into theprocess chamber 1 through a vacuum delivery medium. Optionally, the type of vacuum transfer medium is a continuous vacuum or a discontinuous vacuum.

As shown in fig. 2, thegenerator 31 may specifically be an electron gun, which may specifically be used for generating an electron beam, which is generally emitted by a hot cathode and accelerated by a high voltage power supply to obtain an electron beam with a required energy. The focusing of the electron beam is then achieved by the action of the axially directed focusing coil magnetic field, after which the electron beam may be transmitted by atransmitter 32. Theconveyor 32 may specifically employ a vacuum transfer medium to transfer the electron beam into theprocess chamber 1, but may be conveyed into theprocess chamber 1 by a discontinuous vacuum system for pulsed electron beams; the continuous electron beam can be transmitted into theprocess chamber 1 through a continuous vacuum system, that is, through multi-stage differential vacuum, the gas pressure is continuously increased in the electron beam transmission path, and finally, the electron beam is led out to a high-pressure area generated by the electron beam plasma. By adopting the design, the electron beam plasma obviously improves the generation efficiency of the plasma and the energy utilization rate due to the special energy feed-in mode of the electron beam plasma. Due to the characteristic of electron beam plasma injected from the outside, the conversion time from the capacitive coupling discharge mode to the inductive coupling discharge mode can be effectively shortened, and the operation cycle time of the atomic layer etching process is shortened. Furthermore, in practical application, when the power in the adsorption step is sufficient, only the electron gun can generate plasma, so that only the etching step needs an inductive coupling discharge mode in one operation period, and the difficulty in realizing the atomic layer etching process is effectively reduced.

In an embodiment of the present application, as shown in fig. 1, the atomic layer etching apparatus further includes a monitoring device 4, and the monitoring device 4 is disposed in theprocess chamber 1 and is configured to monitor a discharge mode of a plasma in theprocess chamber 1. The monitoring device 4 may monitor the discharge mode of theprocess chamber 1, for example, when it is monitored that theprocess chamber 1 is in the inductive coupling discharge mode, the monitoring device 4 may send a monitoring result to thecontrol device 7, and thecontrol device 7 may control the embodiment of the present application to perform the atomic layer etching process. Alternatively, the monitoring device 4 may confirm whether the inductively coupled discharge mode is entered by monitoring the plasma intensity within theprocess chamber 1. By adopting the design, the automation level of the embodiment of the application can be effectively improved, and the process yield of the embodiment of the application can be improved.

In an embodiment of the present application, the upper rf assembly 2 includes adielectric window 21, acoil 22, an upperrf power source 23 and anupper matcher 24; thedielectric window 21 is disposed on the top of theprocess chamber 1, thecoil 22 is disposed on thedielectric window 21, and the upperRF power source 23 is connected to thecoil 22 through theupper matcher 24. Optionally, the system further comprises a lower radio frequency assembly 5, wherein a pedestal 6 for bearing the substrate is arranged in theprocess chamber 1; the lower rf assembly 5 includes a lowerrf power supply 51 and alower matcher 52, wherein the lowerrf power supply 51 is connected to the susceptor 6 through thelower matcher 52 for forming a bias electric field on the susceptor 6.

As shown in fig. 1, the upper rf assembly 2 may include adielectric window 21, acoil 22, an upperrf power supply 23, and anupper matcher 24. The upperrf power source 23 may be configured to provide rf power, and the frequency of the upperrf power source 23 may generally be 2MHz or 13.56MHz, but the embodiment of the present application is not limited thereto, and a person skilled in the art may adjust the setting according to actual situations. The upperrf power source 23 may apply rf power to thecoil 22 through theupper matcher 24 and then may be coupled into theprocess chamber 1 through thedielectric window 21, thereby generating plasma. Alternatively, thedielectric window 21 may be made of a material with a high dielectric constant, such as quartz, but the embodiment of the present application is not limited thereto. The lowerrf power supply 51 may also apply rf power to the susceptor 6 through thelower matcher 52 to form a bias electric field. It should be noted that the embodiments of the present application do not limit the specific implementation of the upper rf module 2 and the lower rf module 5, and the above embodiments are only used to illustrate the principle of the present application, so that a person skilled in the art can adjust the setting according to actual situations.

Based on the same inventive concept, in a second aspect, an embodiment of the present application provides an atomic layer etching method, which is applied to the atomic layer etching apparatus provided in the first aspect, and a flow diagram of the atomic layer etching method is shown in fig. 3, and includes the following steps:

s301: and an adsorption step, namely introducing a first process gas into theprocess chamber 1, starting the upper radio frequency assembly 2 and the auxiliary plasma generating device 3, and controlling the working state of the auxiliary plasma generating device 3 according to the discharge mode of the plasma in theprocess chamber 1 so as to stabilize the plasma in an inductive coupling discharge mode.

S302: and a removing step, namely closing the auxiliary plasma generating device and removing the first process gas.

S303: and etching, namely introducing a second process gas into theprocess chamber 1, starting the upper radio frequency assembly 2 and the auxiliary plasma generating device 3, and controlling the working state of the auxiliary plasma generating device 3 according to the discharge mode of the plasma.

S304: and a cleaning step of cleaning the second process gas and the etching product.

Optionally, monitoring and determining whether the plasma is stable in the inductive coupling discharge mode; if yes, the auxiliary plasma generating device 3 is closed; otherwise, the power of the auxiliary plasma generating device 3 is adjusted to stabilize the plasma in the inductively coupled discharge mode.

Optionally, the first process gas is a reactive gas and the second process gas is an inert gas.

The etching method according to the embodiment of the present application will be described below with reference to fig. 1 to 3. In practical applications, acontrol device 7 may be used to control the whole flow of the atomic layer etching process. Taking gallium nitride etching as an example, one operation cycle may include four steps:

s301: an adsorption step, in which the substrate surface may be exposed to a first process gas, for example, chlorine gas, the first process gas may enter theprocess chamber 1, and form a weak plasma after ionization, and chlorine ions or radicals adsorb active particles to form an adsorption layer.

S302: a removing step of removing the first process gas, in which the first process gas not participating in the reaction in theprocess chamber 1 may be removed, and evacuating theprocess chamber 1.

S303: and an etching step, wherein the adsorption layer can be exposed to a second process gas, for example, inert gas such as argon can be adopted, plasma is formed after ionization, the surface of the substrate is bombarded by argon ions to generate sputtering, and meanwhile atoms on the top layer of the substrate are removed.

S304: a cleaning step, which may clean the etching products in theprocess chamber 1, and may remove the second process gas, and may evacuate theprocess chamber 1 to complete the current operation cycle.

The atomic layer etching process includes two plasma generation stages, which are step S301 and step S303. In order to improve the radio frequency coupling efficiency, the upper radio frequency component 2 is adopted to excite the plasma in the starting process, then the plasma is monitored through the monitoring device 4 according to the discharge mode of the plasma, and when the plasma is monitored to be in the capacitive coupling discharge mode, thecontrol device 7 adjusts the working state of the auxiliary plasma generating device 3, for example, the auxiliary plasma generating device 3 is started or the running power of the auxiliary plasma generating device is increased, so that theprocess chamber 1 can rapidly enter and be stabilized in the inductive coupling discharge mode.

The auxiliary plasma generating device 3, for example, an ultraviolet lamp, is used, when the ultraviolet lamp works, filaments at two ends of the lamp tube can emit a large amount of electrons, the electrons are conveyed into theprocess chamber 1 through theinternal conveyer 32, the electrons move back and forth under the action of a high-voltage alternating electric field, if the energy is enough, impact ionization can be generated when the electrons collide with gas atoms, and thus the collided electrons and gas ions are added to move under the action of the electric field to knock out more ions, so that plasma is formed. At the same time, the particles in the plasma will also move back and forth, so that more ions are generated by collision, and the impedance Rcap of the plasma will be rapidly reduced, wherein Rcap includes capacitive heating (ohmic heating and random heating) of electrons. The conversion efficiency ξ from the capacitive coupling discharge mode to the inductive coupling discharge mode in the discharge of the upper radio frequency component 2 can be approximately expressed as:

according to the formula (1), when the plasma impedance Rcap is rapidly reduced, the conversion efficiency of the capacitive-inductive coupling discharge mode is improved, and the matching arrival time is shortened, the plasma rapidly enters a plasma stable state, so that the process time of the step S301 and the step S303 is shortened, the plasma starting state does not need to be maintained in the step S302, the residual process gas can be removed more thoroughly, and the reaction separation between the steps required by the atomic layer etching process is realized. Further, since the plasma density required in step S301 is low and is in a weak plasma state, the required ion energy is generally lower than 10eV, and when the power of the ultraviolet lamp is sufficient, only the ultraviolet lamp is used to generate plasma, so that only step S303 needs an inductive coupling discharge mode in one operation cycle, thereby effectively reducing the difficulty in implementing the atomic layer etching process.

By applying the embodiment of the application, at least the following beneficial effects can be realized:

by the aid of the auxiliary plasma generation device, the process chamber can quickly enter the inductive coupling discharge mode on the basis of work of the upper radio frequency assembly, time for the plasma to enter the inductive coupling discharge mode is shortened, time of each operation period of the atomic layer is shortened, and accordingly atomic layer etching efficiency and process yield are improved. Furthermore, due to the adoption of the design, the plasma starting state in the removing step in the prior art can be avoided, the residual process gas can be more thoroughly removed after each step of the operation period, the reaction separation among the steps required by the atomic layer etching process is really realized, and the accurate control on the process damage and the uniformity is facilitated.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present invention.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the description herein, particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is only a few embodiments of the present application and it should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present application, and that these improvements and modifications should also be considered as the protection scope of the present application.

Claims (10)

1. An atomic layer etching apparatus, comprising: the plasma processing device comprises a process chamber, an upper radio frequency assembly and an auxiliary plasma generating device;

the upper radio frequency assembly is used for applying radio frequency power to the process chamber so as to excite the process gas entering the process chamber into plasma;

the auxiliary plasma generating device is used for transmitting electrons to the process chamber when the plasma is in a capacitive coupling discharge mode so as to shorten the time for the plasma to enter an inductive coupling discharge mode and stabilize the plasma in the inductive coupling discharge mode.

2. The atomic layer etching apparatus according to claim 1, wherein the auxiliary plasma generating device comprises a generator and a transmitter, the generator being connected to the process chamber through the transmitter.

3. The atomic layer etching apparatus according to claim 2, wherein the auxiliary plasma generating device further comprises a ballast electrically connected to the generator for adjusting a current of the generator.

4. The atomic layer etching apparatus according to claim 3, wherein the generator is an ultraviolet lamp.

5. The atomic layer etching apparatus of claim 2, wherein the generator is an electron gun and the conveyor vacuum-transports the medium; the electron gun is used for generating an electron beam and transmitting the electron beam into the process chamber through the vacuum transmission medium.

6. The atomic layer etching apparatus according to claim 1, further comprising a monitoring device disposed within the process chamber for monitoring a discharge pattern of a plasma within the process chamber.

7. The atomic layer etching device according to any of claims 1 to 6, further comprising a lower radio frequency assembly, wherein a susceptor for carrying a substrate is disposed within the process chamber; the lower radio frequency assembly comprises a lower radio frequency power supply and a lower matcher, wherein the lower radio frequency power supply is connected with the base through the lower matcher and is used for forming a bias electric field on the base.

8. An atomic layer etching method applied to the atomic layer etching apparatus according to any one of claims 1 to 7, comprising the steps of:

an adsorption step, namely introducing first process gas into the process chamber, starting the upper radio frequency assembly and the auxiliary plasma generating device, and controlling the working state of the auxiliary plasma generating device according to the discharge mode of the plasma in the process chamber so as to stabilize the plasma in an inductive coupling discharge mode;

a removing step, namely closing the auxiliary plasma generating device and removing the first process gas;

etching, namely introducing a second process gas into the process chamber, starting the upper radio frequency assembly and the auxiliary plasma generating device, and controlling the working state of the auxiliary plasma generating device according to the discharge mode of the plasma;

and a cleaning step of cleaning the second process gas and the etching product.

9. The method of claim 8, wherein controlling the operating state of the auxiliary plasma generating device according to the discharge mode of the plasma comprises:

monitoring and judging whether the plasma is stable in an inductive coupling discharge mode; if yes, the auxiliary plasma generating device is closed; if not, adjusting the power of the auxiliary plasma generating device to stabilize the plasma in the inductive coupling discharge mode.

10. The method of claim 9, wherein the first process gas is a reactive gas and the second process gas is an inert gas.

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